Simplified risk stratification based on cardiopulmonary exercise test: A Spanish two-center experience.

A simplified 4-strata risk stratification approach based on three variables is widespread in pulmonary arterial hypertension (PAH) at follow-up. This study aimed to assess the impact of replacing the 6-min walk test (6MWT) with the peak 02 uptake evaluated by the cardiopulmonary exercise test (CPET) on risk stratification by this scale. We included 180 prevalent patients with PAH from two reference hospitals in Spain, followed up between 2006 and 2022. Patients were included if all the variables of interest were available within a 3-month period on the Spanish Registry of Pulmonary Arterial Hypertension (REHAP): functional class (FC); NT-proBNP; 6MWT; and CPET. The original 4-strata model (NT-proBNP, 6MWT, FC) identified most patients at low or intermediate-low risk (36.7% and 51.1%, respectively). Notably, the modified scale (NT-proBNP, CPET, FC) improved the identification of patients at intermediate-high risk up to 18.9%, and at high risk up to 1.1% in comparison with the previous 12.2% and 0.0% in the original scale. This new model increased the number of patients correctly classified into higher-risk strata (positive NRI of 0.06), as well as classified more patients without events in lower-risk strata (negative NRI of 0.04). The proposed score showed a slightly superior prognostic capacity compared with the original model (Harrel's C-index 0.717 vs. 0.709). Using O2 uptake instead of distance walked in the 6MWT improves the identification of high-risk patients using the 4-strata scale. This change could have relevant prognostic implications and lead to changes in the specific treatment of PAH.

The importance of data in Pulmonary Arterial Hypertension: from international registries to Machine Learning. / La importancia de los datos en la hipertensión arterial pulmonar: de los registros internacionales al machine learning.

Real-world registries have been critical to building the scientific knowledge of rare diseases, including Pulmonary Arterial Hypertension (PAH). In the past 4 decades, a considerable number of registries on this condition have allowed to improve the pathology and its subgroups definition, to advance in the understanding of its pathophysiology, to elaborate prognostic scales and to check the transferability of the results from clinical trials to clinical practice. However, in a moment where a huge amount of data from multiple sources is available, they are not always taken into account by the registries. For that reason, Machine Learning (ML) offer a unique opportunity to manage all these data and, finally, to obtain tools that may help to get an earlier diagnose, to help to deduce the prognosis and, in the end, to advance in Personalized Medicine. Thus, we present a narrative revision with the aims of, in one hand, summing up the aspects in which data extraction is important in rare diseases -focusing on the knowledge gained from PAH real-world registries- and, on the other hand, describing some of the achievements and the potential use of the ML techniques on PAH.

Real-World Management of Patients with Pulmonary Arterial Hypertension: Insights from EXPOSURE.

INTRODUCTION: Further insights into real-world management and outcomes of patients with pulmonary arterial hypertension (PAH) are needed. This interim analysis of the ongoing, multicentre, prospective EXPOSURE (EUPAS19085) observational study describes characteristics, treatment patterns and outcomes of patients with PAH initiating a new PAH-specific therapy in Europe/Canada. METHODS AND RESULTS: All analyses were descriptive. In total, 1944 patients with follow-up information were included; the majority were female, with World Health Organization functional class II/III symptoms and with idiopathic PAH or connective tissue disease-associated PAH. Most incident patients (N = 1100; diagnosed for ≤ 6 months) initiated treatment as monotherapy (48%) or double therapy (43%). Of those initiating monotherapy, 38% (199/530) escalated to double therapy (median [Q1, Q3] time to escalation 3.4 [1.9, 6.6] months), and of those initiating double therapy, 17% (78/457) escalated to triple therapy (median [Q1, Q3] time to escalation 7.0 [3.4, 12.7] months) during the observation period (median [Q1, Q3]: 17.0 [7.5, 29.9] months). The majority of the 834 prevalent patients (diagnosed > 6 months) entered the study on initiation of combination therapy and most did not change treatment regimen during the observation period (median [Q1, Q3]: 19.6 [10.2, 32.2] months). One-year survival was 88% for incident patients and 90% for prevalent patients. CONCLUSIONS: Results from EXPOSURE suggest a shift towards combination therapy and the alignment of real-world treatment patterns with current guideline recommendations. While survival estimates are encouraging, the extent of monotherapy use at treatment initiation and follow-up highlight an opportunity for further improvements through optimisation of treatment strategies in line with current guidelines. A graphical abstract is also available with this article. TRIAL REGISTRATION NUMBER: EUPAS19085.

Pulmonary arterial hypertension (PAH) is a progressive disease. Clinical guidelines recommend that most patients start treatment with a combination of different PAH medications. While there is no cure for PAH, these medications help to control symptoms and slow disease worsening. To understand treatments currently used in clinical practice, we analysed data from EXPOSURE (EUPAS19085), an ongoing study collecting information from patients starting a new PAH medication in Europe and Canada. Most patients in the study were female, with World Health Organization functional class II/III symptoms, and idiopathic (unknown cause) PAH or PAH associated with connective tissue disorders. Among 1100 patients who were 'recently diagnosed' (diagnosed with PAH in the past 6 months), 88% were alive after 1 year. We found that 48% started treatment with one PAH medication, and 38% of those patients had a second medication prescribed within a median period of 3 months. Among the 457 'recently diagnosed' patients treated with two PAH medications when they entered the study, 17% had a third medication prescribed within a median period of 7 months. Among 834 patients with 'established PAH' (diagnosed more than 6 months ago), 90% were alive after 1 year. Most entered the study when they started a third medication and did not have further changes in treatment. Our findings show that patients with PAH are often treated with one medication in clinical practice as well as a combination of medications. While survival rates are encouraging, the extent to which one PAH medication is used suggests there is room for treatment improvement.

Triple vasodilator therapy in pulmonary arterial hypertension associated with congenital heart disease.

OBJECTIVE: This study assessed the long-term effects of triple therapy with prostanoids on patients with pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD), as there is limited information on the safety and efficacy of this treatment approach. METHODS: A retrospective cohort study was conducted on patients with PAH-CHD who were actively followed up at our centre. All patients were already receiving dual combination therapy at maximum doses. Clinical characteristics, including functional class (FC), 6-minute walking test distance (6MWTD) and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels, were documented before initiating triple therapy and annually for a 2-year follow-up period. RESULTS: A total of 60 patients were included in the study, with a median age of 41 years and 68% being women. Of these, 32 had Eisenmenger syndrome, 9 had coincidental shunts, 18 had postoperative PAH and 1 had a significant left-to-right shunt. After 1 year of triple combination initiation, a significant improvement in 6MWTD was observed (406 vs 450; p=0.0027), which was maintained at the 2-year follow-up. FC improved in 79% of patients at 1 year and remained stable in 76% at 2 years. NT-proBNP levels decreased significantly by 2 years, with an average reduction of 199 ng/L. Side effects were experienced by 33.3% of patients but were mostly mild and manageable. Subgroup analysis showed greater benefits in patients without Eisenmenger syndrome and those with pre-tricuspid defects. CONCLUSIONS: Triple therapy with prostanoids is safe and effective for patients with PAH-CHD, improving FC, 6MWTD and NT-proBNP levels over 2 years. The treatment is particularly beneficial for patients with pre-tricuspid defects and non-Eisenmenger PAH-CHD.

Value of exercise right heart catheterization in the differential diagnosis of chronic thromboembolic pulmonary disease.

INTRODUCTION AND OBJECTIVES: Chronic thromboembolic disease refers to the presence of chronic thrombotic pulmonary vascular thrombosis without pulmonary hypertension (PH) at rest but with exercise limitation after pulmonary embolism (PE). Our aim was to evaluate the hemodynamic response to exercise in these patients and its correlation with the values reached in cardiopulmonary exercise testing. METHODS: We included symptomatic patients with persistent pulmonary thrombosis after PE. We excluded patients with left heart disease or significant PH (mean pulmonary arterial pressure [mPAP] >25mmHg, pulmonary vascular resistance >3 WU, and pulmonary capillary wedge pressure [PCWP] >15mmHg). Cardiopulmonary exercise testing and exercise right heart catheterization were performed. Exercise-induced precapillary PH was defined as mPAP/CO slope >3 and PCWP/CO slope <2mmHg/l/min. The hemodynamic response and the values obtained in cardiopulmonary exercise testing were compared between patients with and without exercise-induced precapillary PH. RESULTS: We studied 36 patients; 4 were excluded due to incomplete hemodynamic data. Out of the 32 patients analyzed; 3 developed a pathological increase in PCWP. Among the remaining 29 patients (mean age, 49.4±13.7 years, 34.5% women), 13 showed exercise-induced PH. Resting mPAP was higher in those who developed exercise-induced PH (23.3±5.4 vs 19.0±3.8mmHg; P=.012), although CO was similar in the 2 groups. Patients with exercise-induced PH exhibited data of ventilatory inefficiency with reduced values of end-tidal CO2 pressure at the anaerobic threshold (32.8±3.0 vs 36.2±3.3mmHg; P=.021) and a higher Ve/VCO2 slope (34.2±4.8 vs 30.7±5.0; P=.049). CONCLUSIONS: Exercise limitation and ventilatory inefficiency could be attributable to exercise-induced precapillary PH in a subgroup of patients with persistent pulmonary thrombosis and dyspnea.

Seven Additional Patients with SOX17 Related Pulmonary Arterial Hypertension and Review of the Literature.

Pulmonary arterial hypertension (PAH) is an infrequent disorder characterized by high blood pressure in the pulmonary arteries. It may lead to premature death or the requirement for lung and/or heart transplantation. Genetics plays an important and increasing role in the diagnosis of PAH. Here, we report seven additional patients with variants in SOX17 and a review of sixty previously described patients in the literature. Patients described in this study suffered with additional conditions including large septal defects, as described by other groups. Collectively, sixty-seven PAH patients have been reported so far with variants in SOX17, including missense and loss-of-function (LoF) variants. The majority of the loss-of-function variants found in SOX17 were detected in the last exon of the gene. Meanwhile, most missense variants were located within exon one, suggesting a probable tolerated change at the amino terminal part of the protein. In addition, we reported two idiopathic PAH patients presenting with the same variant previously detected in five patients by other studies, suggesting a possible hot spot. Research conducted on PAH associated with congenital heart disease (CHD) indicated that variants in SOX17 might be particularly prevalent in this subgroup, as two out of our seven additional patients presented with CHD. Further research is still necessary to clarify the precise association between the biological pathway of SOX17 and the development of PAH.

Evolución y pronóstico de la insuficiencia tricuspídea moderada-grave tras tromboendarterectomía pulmonar o angioplastia de arterias pulmonares / Outcome of moderate-severe tricuspid regurgitation after pulmonary endarterectomy or balloon pulmonary angioplasty

Introducción y objetivos: No está definido el abordaje de la insuficiencia tricuspídea (IT) funcional moderada-grave en los pacientes con hipertensión pulmonar tromboembólica crónica tras la tromboendarterectomía pulmonar (TEA) o angioplastia con balón de las arterias pulmonares (ABAP). El objetivo de este estudio es analizar la evolución y los predictores de IT residual tras el procedimiento, así como su impacto pronóstico. Métodos: Estudio observacional unicéntrico. Se incluyó a 72 pacientes sometidos a TEA y 20 que completaron el programa de ABAP con diagnóstico de hipertensión pulmonar tromboembólica crónica y presentaban IT moderada-grave antes del procedimiento intervencionista. Resultados: La prevalencia de IT moderada-grave tras el procedimiento fue del 29%, sin diferencias entre los tratados con TEA o ABAP (el 30,6 frente al 25%; p=0,78). En el grupo con IT persistente se hallaron mayores presión arterial pulmonar media (40,2± 1,9 frente a 28,5±1,3mmHg; p<0,001), resistencia vascular pulmonar (472 [347-710] frente a 282 [196-408] dyn·s/cm5; p <0,001) y área de la aurícula derecha (23,0 [21-31] frente a 16,0 [14,0-20,0]; p <0,001) tras el procedimiento comparado con el de pacientes con IT ausente-ligera. La resistencia vascular pulmonar> 400dyn.s/cm5 y el área de la aurícula derecha> 22 cm2 tras el procedimiento se asociaron de manera independiente con la persistencia de la IT, pero no se identificaron predictores antes de la intervención. La IT moderada-grave residual y la presión pulmonar media> 30mmHg se asociaron con mayor mortalidad en 3 años de seguimiento. Conclusiones: La IT moderada-grave residual posterior a TEA o ABAP se asoció con la persistencia de una mayor poscarga y un persistente remodelado desfavorable de las cámaras cardiacas derechas tras el procedimiento. La IT moderada-grave y la hipertensión pulmonar residual se asociaron con un peor pronóstico a 3 años. (AU)

Introduction and objectives: The management of persistent moderate-severe tricuspid regurgitation (TR) in patients with chronic thromboembolic pulmonary hypertension after treatment with pulmonary endarterectomy (PEA) or balloon pulmonary angioplasty (BPA) is not well defined. This study aimed to analyze the progression and predictors of significant persistent postintervention TR and its prognostic impact. Methods: This single-center observational study included 72 patients undergoing PEA and 20 who completed a BPA program with a previous diagnosis of chronic thromboembolic pulmonary hypertension and moderate-to-severe TR. Results: The postintervention prevalence of moderate-to-severe TR was 29%, with no difference between the PEA- or BPA-treated groups (30.6% vs 25% P=.78). Compared with patients with absent-mild postprocedure TR, those with persistent TR had higher mean pulmonary arterial pressure (40.2±1.9 vs 28.5±1.3mmHg P <.001), pulmonary vascular resistance (472 [347-710] vs 282 [196-408] dyn.s/cm5; P <.001), and right atrial area (23.0 [21-31] vs 16.0 [14.0-20.0] P <.001). The variables independently associated with persistent TR were pulmonary vascular resistance> 400 dyn.s/cm5 and postprocedure right atrial area> 22cm2. No preintervention predictors were identified. The variables associated with increased 3-year mortality were residual TR and mean pulmonary arterial pressure> 30mmHg. Conclusions: Residual moderate-to-severe TR following PEA-PBA was associated with persistently high afterload and unfavorable postintervention right chamber remodeling. Moderate-to-severe TR and residual pulmonary hypertension were associated with a worse 3-year prognosis. (AU)

Predictors of the response to phosphodiesterase-5 inhibitors in pulmonary arterial hypertension: an analysis of the Spanish registry.

BACKGROUND: Achieving and maintaining a low-risk profile is associated with favorable outcome in pulmonary arterial hypertension (PAH). The effects of treatment on risk profile are variable among patients. OBJECTIVE: To Identify variables that might predict the response to treatment with phosphodiesterase-5 inhibitors (PDE-5i) in PAH. METHODS: We carried out a cohort analysis of the Spanish PAH registry in 830 patients diagnosed with PAH that started PDE5i treatment and had > 1 year follow-up. 644 patients started PDE-5i either in mono- or add-on therapy and 186 started combined treatment with PDE-5i and endothelin receptor antagonist (ERA). Responders were considered when at 1 year they: (1) were alive; (2) did not present clinical worsening; and (3) improved European Society of Cardiology/European Respiratory Society (ESC/ERS) risk score or remained in low-risk. Univariate and multivariate logistic regression models were used to analyze variables associated with a favorable response. RESULTS: Two hundred and ten patients (33%) starting PDE-5i alone were classified as responders, irrespective of whether it was mono- or add-on therapy. In addition to known predictors of PAH outcome (low-risk at baseline, younger age), male sex and diagnosis of portopulmonary hypertension (PoPH) or HIV-PAH were independent predictors of favorable response to PDE-5i. Diffusing capacity for carbon monoxide (DLco) ≤ 40% of predicted was associated with an unfavorable response. When PDE-5i were used in upfront combination, 58% of patients were responders. In this group, diagnosis of idiopathic PAH (IPAH) was an independent predictor of favorable response, whereas connective tissue disease-PAH was associated with an unfavorable response. CONCLUSION: Male sex and diagnosis of PoPH or HIV-PAH are predictors of favorable effect of PDE-5i on risk profile when used as mono- or add-on therapy. Patients with IPAH respond more favorably to PDE-5i when used in upfront combination. These results identify patient profiles that may respond favorably to PDE-5i in monotherapy and those who might benefit from alternative treatment strategies.

Balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension: a clinical consensus statement of the ESC working group on pulmonary circulation and right ventricular function.

The current treatment algorithm for chronic thromboembolic pulmonary hypertension (CTEPH) as depicted in the 2022 European Society of Cardiology (ESC)/European Respiratory Society (ERS) guidelines on the diagnosis and treatment of pulmonary hypertension (PH) includes a multimodal approach of combinations of pulmonary endarterectomy (PEA), balloon pulmonary angioplasty (BPA) and medical therapies to target major vessel pulmonary vascular lesions, and microvasculopathy. Today, BPA of >1700 patients has been reported in the literature from centers in Asia, the US, and also Europe; many more patients have been treated outside literature reports. As BPA becomes part of routine care of patients with CTEPH, benchmarks for safe and effective care delivery become increasingly important. In light of this development, the ESC Working Group on Pulmonary Circulation and Right Ventricular Function has decided to publish a document that helps standardize BPA to meet the need of uniformity in patient selection, procedural planning, technical approach, materials and devices, treatment goals, complications including their management, and patient follow-up, thus complementing the guidelines. Delphi methodology was utilized for statements that were not evidence based. First, an anatomical nomenclature and a description of vascular lesions are provided. Second, treatment goals and definitions of complete BPA are outlined. Third, definitions of complications are presented which may be the basis for a standardized reporting in studies involving BPA. The document is intended to serve as a companion to the official ESC/ERS guidelines.

Outcome of moderate-severe tricuspid regurgitation after pulmonary endarterectomy or balloon pulmonary angioplasty.

INTRODUCTION AND OBJECTIVES: The management of persistent moderate-severe tricuspid regurgitation (TR) in patients with chronic thromboembolic pulmonary hypertension after treatment with pulmonary endarterectomy (PEA) or balloon pulmonary angioplasty (BPA) is not well defined. This study aimed to analyze the progression and predictors of significant persistent postintervention TR and its prognostic impact. METHODS: This single-center observational study included 72 patients undergoing PEA and 20 who completed a BPA program with a previous diagnosis of chronic thromboembolic pulmonary hypertension and moderate-to-severe TR. RESULTS: The postintervention prevalence of moderate-to-severe TR was 29%, with no difference between the PEA- or BPA-treated groups (30.6% vs 25% P=.78). Compared with patients with absent-mild postprocedure TR, those with persistent TR had higher mean pulmonary arterial pressure (40.2±1.9 vs 28.5±1.3mmHg P <.001), pulmonary vascular resistance (472 [347-710] vs 282 [196-408] dyn.s/cm5; P <.001), and right atrial area (23.0 [21-31] vs 16.0 [14.0-20.0] P <.001). The variables independently associated with persistent TR were pulmonary vascular resistance> 400 dyn.s/cm5 and postprocedure right atrial area> 22cm2. No preintervention predictors were identified. The variables associated with increased 3-year mortality were residual TR and mean pulmonary arterial pressure> 30mmHg. CONCLUSIONS: Residual moderate-to-severe TR following PEA-PBA was associated with persistently high afterload and unfavorable postintervention right chamber remodeling. Moderate-to-severe TR and residual pulmonary hypertension were associated with a worse 3-year prognosis.

European Society of Cardiology quality indicators for the care and outcomes of adults with pulmonary arterial hypertension. Developed in collaboration with the Heart Failure Association of the European Society of Cardiology.

AIMS: To develop a suite of quality indicators (QIs) for the evaluation of the care and outcomes for adults with pulmonary arterial hypertension (PAH). METHODS AND RESULTS: We followed the European Society of Cardiology (ESC) methodology for the development of QIs. This included (i) the identification of key domains of care for the management of PAH, (ii) the proposal of candidate QIs following systematic review of the literature, and (iii) the selection of a set of QIs using a modified Delphi method. The process was undertaken in parallel with the writing of the 2022 ESC/European Respiratory Society (ERS) guidelines for the diagnosis and treatment of pulmonary hypertension and involved the Task Force chairs, experts in PAH, Heart Failure Association (HFA) members and patient representatives. We identified five domains of care for patients with PAH: structural framework, diagnosis and risk stratification, initial treatment, follow-up, and outcomes. In total, 23 main and one secondary QIs for PAH were selected. CONCLUSION: This document presents the ESC QIs for PAH, describes their development process and offers scientific rationale for their selection. The indicators may be used to quantify and improve adherence to guideline-recommended clinical practice and improve patient outcomes.

Novel Loss-of-Function KCNA5 Variants in Pulmonary Arterial Hypertension.

Reduced expression and/or activity of Kv1.5 channels (encoded by KCNA5) is a common hallmark in human or experimental pulmonary arterial hypertension (PAH). Likewise, genetic variants in KCNA5 have been found in patients with PAH, but their functional consequences and potential impact on the disease are largely unknown. Herein, this study aimed to characterize the functional consequences of seven KCNA5 variants found in a cohort of patients with PAH. Potassium currents were recorded by patch-clamp technique in HEK293 cells transfected with wild-type or mutant Kv1.5 cDNA. Flow cytometry, Western blot, and confocal microscopy techniques were used for measuring protein expression and cell apoptosis in HEK293 and human pulmonary artery smooth muscle cells. KCNA5 variants (namely, Arg184Pro and Gly384Arg) found in patients with PAH resulted in a clear loss of potassium channel function as assessed by electrophysiological and molecular modeling analyses. The Arg184Pro variant also resulted in a pronounced reduction of Kv1.5 expression. Transfection with Arg184Pro or Gly384Arg variants decreased apoptosis of human pulmonary artery smooth muscle cells compared with the wild-type cells, demonstrating that KCNA5 dysfunction in both variants affects cell viability. Thus, in addition to affecting channel activity, both variants were associated with impaired apoptosis, a crucial process linked to the disease. The estimated prevalence of dysfunctional KCNA5 variants in the PAH population analyzed was around 1%. The data indicate that some KCNA5 variants found in patients with PAH have critical consequences for channel function, supporting the idea that KCNA5 pathogenic variants may be a causative or contributing factor for PAH.